Estimated Position (video)
You have calculated your dead reckoning position, but you are sailing in tidal waters, so how do you find out where you are now?
Following on from our dead reckoning (D.R.) tutorial, were you plotted your position using the direction the boat travelled and the distance, we now need to factor in the tidal stream. The tidal stream always has two components the direction and the rate, also known as the set and drift. To do this you simply draw this in at the end of your dead reckoning and this gives you your Estimated Position (E.P.)
E.P. = D.R. + Tide